When European Rail Traffic Management System (ERTMS) was being developed the first pieces of onboard equipment were rather large, about the size of a domestic refrigerator, many said. At the time there was no question that the signalling companies had done extremely well to get all the necessary kit into such a small space. Given the pace of computing technology, can we do rather better now – and is there really a need for smaller onboard installations?
Invensys Rail, now part of Siemens, pointed the way forward with its LYRA onboard installation, which was vastly smaller than anything else the market had seen two years ago. About the size of a desktop PC case, it was small enough to be fitted into even the most space starved locomotives and rolling stock. Given that in the four years since it was launched in 2010 that computing power available in a tablet PC format is so much greater, with suitable provision for the standard interfaces needed, could we see an onboard ERTMS package able to be fitted in the space under a passenger train seat?
Technologically it appears perfectly feasible. The computing requirements of ERTMS are not all that great, so providing that power in the smallest possible installation would appear to make sense from space considerations alone. Can such small devices be made robust enough for railway applications? There seems no reason why they can’t: military specification equipment is robust enough for those demands, and would surely be appropriate, with modification, for rail use.
But what benefits would there really be from going down such a road? Most modern trains are designed with ERTMS (or CBTC or PTC) provision in mind so space isn’t really a major issue for new rolling stock. For the retro-fit market though, every cubic centimetre you save can be valuable. Fitting ERTMS onboard equipment to older locomotives can be a particular challenge, and it is easier to find space for something the size of a small PC than a refrigerator in a bodyshell. That is an obvious advantage.
Another advantage is that there will be an ongoing requirement for non-ERTMS fitted vehicles to travel over ERTMS fitted routes for occasional maintenance or special duties. The cost of fitting ERTMS to a locomotive that spends 99% of its working life on legacy routes is hard to justify – but what if you could fit the necessary sensors and interfaces at an overhaul and then, when needed, plug in a modular ERTMS computing platform for those rare journeys? It would save money for operators and track authorities who may have to fund onboard installation for legacy stock and reduce the complexity of day to day operation on non-ERTMS lines, yet still retain a capability for ERTMS operation where needed. It could even be a solution for main line heritage operations such as those in the United Kingdom, Germany and Poland (amongst others) where occasional outings of historical vehicles would otherwise effectively be blocked by ERTMS.
Is any of this possible, feasible or sensible? Let us know your thoughts….